Spin-on, twist-on, quick-change disposable type filters are used in numerous liquid and pneumatic applications thoughout the agricultural, commercial and industrial market places. Prior art disposable filters require an associated mounting and/or fluid distribution head assembly. Most of these filter products are manufactured utilizing a housing can made by deep-draw forming thin gauge malleable metals. This design limits the performance capabilities of current spin-on, twist-on, type disposable products to the present production technologies of the metal forming industry and to the molecular characteristics of a limited number of specific malleable metals. Prior art uses a stamped steel or cast cover plate to secure the housing to a mounting and distribution head assembly wherein this plate typically has a threaded center hole and is welded and/or crimp sealed to a can to form the filter housing. These techniques for sealing and connecting the can to the plate, plus the structural limits of thin gauge malleable metals, generally restrict the applicational uses of prior art spin-on, twist-on, disposable filters. Some new high pressure, high-strength, disposable filter housings have been developed for some narrowly defined markets and applications. However, even these newer high-strength filters remain applicationally limited to typically the 1,000 psi burst range because of the use of deep-drawn thin gauge metal cans.
Another typical design common to prior art spin-on, twist-on, disposable type filters is the necessity of installing a separate filter element in conjunction with various separator devices, in a housing can. A separate and segregated internal filter element cartridge is subject to different cyclical operational loads than those experienced by the filter housing. Most current internal filter cartridge designs do not properly protect against seal distortion or wear deterioration caused by application flow dynamics and vibration. Such seal distortion and wear deterioration lessens a filters contamination removal efficiency by allowing contaminated fluid to by-pass the filter medium.
Examples of prior art limitations can be found in U.S. Pat. No. 4,719,012, U.S. Pat. No. 4,743,374 (issued as an improvement over U.S. Pat. No. 4,369,113), and U.S. Pat. No. 4,735,716 which offer varying degrees of high-strength and quick-change capability. Two of these designs incorporate the continued use of deep-drawn thin gauge malleable metal cans, with all three requiring a separate internal filtering element. Even though burst pressure ratings are in the 1,000 psi range, prior art filter designs continue to leave a major product void in the spin-on, twist-on, quick-change high-strength disposable filter market.
A need exists for a structurally improved spin-on, twist-on quick-change, quick-disconnect type disposable filter with higher pressure capability, a better fatigue rating, a design that eliminates the need for a separate and segregated internal filter cartridge, and a filter product that decreases by-passing fluid losses caused by distorted or deteriorated internal element seals. The present tube filter invention is designed to overcome one or more of the problems as set forth above.